While this model seems to address many of the issues
that have been raised, and offers some hope of being
massaged into a solid classifactory and predictive
model, it is not without its weaknesses. There are
several criticisms that might be made about the model,
including:

The structural layer seems to be somewhat heavy
and the application layer somewhat light. For
example, ANS.1 and SGML are very different levels
of structuring. Similarly, a case might be made
for movinng CALS and STEP to the structural
level, leaving little to be placed at the
application level. One might suggest that
structure become "generic structural" and
application become "domain structural."

The model does little as currently configured to
address the division or management of standards
in what must be defined as two of the most
important application areas: structured records
(data bases) and documents. Indeed there is no
clear column for structured records.

There is no precedent for the linkage of
operation standards to data representation
standards in this way. In some ways, the
appendage of tightly coupled operations begins to
expand this reference model to a vast amount of
the standardization landscape.

At a theoretic level, there is assumed to be a
reasonable progression from signal to data to
information and knowledge. The signal/data
transformation makes good sense in thinking about
the low levels of data interchnage standards.
Many people have suggested that organized data is
information and information with methodology is
knowledge. This suggests a more semantically
attractive axis than the atomic, elemental,
structural division, but has the problem of
collapsing all operational standards into the
highest level, which itself creates problems.

There are more problems, but I'm sure involved readers
will be quick to see and point them out. At the same
time, the issue is not the final form of a reference
model but the agreement about the importance of
addressing the issue. The author welcomes comments,
criticisms and alternative proposals. The interested
reader will find more attached to the authors homepage
at http://www.sis.pitt.edu/ spring.
Next: About this document Up:A Reference Model for Previous: A Proposal